1. Field of the Invention
The present invention relates to a liquid crystal display (LCD) device, and more particularly, to a substrate having a pixel electrode in an LCD device.
2. Discussion of the Related Art
Generally, an LCD device includes first and second substrates facing each other, and a liquid crystal layer formed between the first and second substrates. When a voltage is applied to the LCD device, an alignment of liquid crystal molecules in the liquid crystal layer is changed so as to control light transmittance, to thereby display picture images.
Hereinafter, a related art LCD device will be explained with reference to the accompanying drawings.
FIG. 1 is a cross sectional view of a related art LCD device.
As shown in FIG. 1, a related art LCD device includes a first substrate 10, a second substrate 30, and a liquid crystal layer 70 formed between the first and second substrates 10 and 30.
The first substrate 10 includes a thin film transistor (not shown), and a pixel electrode 12 connected to the thin film transistor. Also, an alignment layer 50 for initial alignment of the liquid crystal layer 70 is formed above the pixel electrode 12.
The second substrate 30 includes a light-shielding layer 32 to prevent light leakage, a color filter layer 34 of R, G and B color resists formed on the light-shielding layer 32, and a common electrode 36 formed on the color filter layer 34. In addition, the alignment layer 50 for initial alignment of the liquid crystal layer 70 is formed on the common electrode 36.
Hereinafter, a method for forming the first substrate 10 on which the pixel electrode 12 is formed will be explained as follows.
FIGS. 2A to 2F are cross sectional views illustrating a method for forming the first substrate having the pixel electrode in the related art LCD device. Description of the thin film transistor is omitted in FIGS. 2A to 2F.
First, as shown in FIG. 2A, an electrode layer 12a for a pixel electrode is formed on the first substrate 10, and a photoresist layer 20a is formed on the electrode layer 12a. 
Next, as shown in FIG. 2B, after positioning a predetermined mask 25 above the first substrate 10, light is applied to the photoresist layer 20a. 
As shown in FIG. 2C, a predetermined photoresist pattern 20 is formed.
As shown in FIG. 2D, the electrode layer 12a for pixel electrode is patterned by using the photoresist pattern 20 as a mask, to thereby form a pattern of the pixel electrode 12.
As shown in FIG. 2E, the pixel electrode 12 is formed by removing the photoresist pattern 20.
As shown in FIG. 2F, the alignment layer 50 for initial alignment of the liquid crystal is formed above the pixel electrode 12, thereby completing the first substrate of the LCD device.
The above method for forming the first substrate of the LCD device according to the related art uses the additional photoresist pattern 20 to complete the pattern of the pixel electrode 12. Thus, the process for forming the photoresist pattern 20, as shown in FIGS. 2A to 2C, is necessarily required, and the process for removing the photoresist pattern 20, as shown in FIG. 2E, is also required.
Due to the processes for forming and removing the photoresist pattern 20, the related art process is more complicated, and processing time is increased.
For the mass production of the LCD device, there have been continuous research and study to simplify the process so as to decrease the fabrication cost. More particularly, there is a need for a simplified processing method for forming the pixel electrode 12 using the photoresist pattern 20.